Napkin

@mindstone/mcp-server-napkin

Napkin AI visual generation MCP server for Model Context Protocol hosts. Generate professional visuals — diagrams, infographics, and illustrations — from text descriptions, check generation status, and download results through a standardised MCP interface.

Status

• Version: 0.4.1 · npm
• Auth: API key (NAPKIN_API_KEY)
• Tools: 5 (visuals, downloads, styles)
• Surface: cloud-api
• Machine-readable: STATUS.json

Note: The Napkin API is currently a developer preview (see api.napkin.ai). Endpoints and behavior may change; report upstream issues to [email protected]. Older guides reference context_before/context_after parameters — Napkin deprecated these in favor of the single context parameter, which napkin_generate_visual supports.

Requirements

• Node.js 20+
• npm

One-click install

After clicking the button, your host will prompt you to fill: NAPKIN_API_KEY, NAPKIN_REQUEST_TIMEOUT_MS.

{
  "mcpServers": {
    "Napkin": {
      "command": "npx",
      "args": [
        "-y",
        "@mindstone/mcp-server-napkin"
      ],
      "env": {
        "NAPKIN_API_KEY": "",
        "NAPKIN_REQUEST_TIMEOUT_MS": "60000"
      }
    }
  }
}

Quick Start

Install & build

cd <path-to-repo>/connectors/napkin
npm install
npm run build

npx (once published)

npx -y @mindstone/mcp-server-napkin

Local

node dist/index.js

Configuration

Environment variables

• NAPKIN_API_KEY — Napkin AI API key
• MCP_WORKSPACE_PATH — optional workspace path for saving generated visuals
• MCP_HOST_BRIDGE_STATE — optional path to a host bridge state file used for credential management
• MINDSTONE_REBEL_BRIDGE_STATE — backwards-compatible alias for MCP_HOST_BRIDGE_STATE
• NAPKIN_REQUEST_TIMEOUT_MS — optional override (positive integer ms, max 30 min) for the outbound HTTP request timeout applied to Napkin API, host-bridge, and download calls. Default: 60000 (60s). Raise this if you see TIMEOUT errors on slow submits or large downloads; lower it if you want tighter bounds.

Host configuration examples

Claude Desktop / Cursor

{
  "mcpServers": {
    "Napkin": {
      "command": "npx",
      "args": ["-y", "@mindstone/mcp-server-napkin"],
      "env": {
        "NAPKIN_API_KEY": "your-api-key"
      }
    }
  }
}

Local development (no npm publish needed)

{
  "mcpServers": {
    "Napkin": {
      "command": "node",
      "args": ["<path-to-repo>/connectors/napkin/dist/index.js"],
      "env": {
        "NAPKIN_API_KEY": "your-api-key"
      }
    }
  }
}

Tools (5)

Configuration

• configure_napkin_api_key — Configure the Napkin AI API key

Generation

• napkin_generate_visual — Generate a professional visual from text
• napkin_check_status — Check the status of a visual generation request (vendor-authored free text — warning/error messages and visual_query — is wrapped in <untrusted-content> envelopes so hosts treat it as data; codes, IDs, and URLs stay raw, with their machine-identifier charset enforced by response validation)
• napkin_download_visual — Download a generated visual file to disk (existing files are never overwritten — pass a different filename or omit it to auto-generate one). Redirects are re-validated against the Napkin host allow-list before being followed; off-list redirect targets are refused.

Styles

• napkin_list_styles — List the 15 built-in Napkin visual styles (IDs, descriptions, categories) to pick a style_id for napkin_generate_visual. Static catalog; no API key or network call required.

Licence

FSL-1.1-MIT — Functional Source License, Version 1.1, with MIT future licence. The software converts to MIT licence on 2030-04-08.